JP2008057350A - Wind power generator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wind power generator having a high energy converting efficiency with respect to wind velocities in a wide range from a low wind velocity to a high wind velocity. <P>SOLUTION: In this wind power generator, a windmill having a plurality of blades on the rotor head is rotated, and the rotating force of the windmill is transmitted to a generator through a step-up gear to drive the generator for taking out electric energy. Each blade 7 comprises a main blade 8 of streamlined shape in cross section, an auxiliary blade 14 rotatably fitted to the main blade 8 and partly projecting from the upper and lower surfaces of the main blade 8 outward, and a drive means for rotatingly driving the auxiliary blade 14. The auxiliary blade 14 is formed in a cylindrical shape or columnar shape. The auxiliary blade is so installed that its longitudinal direction is set along the longitudinal direction of the main blade 8. A part of the peripheral surface of the auxiliary blade projects from the upper and lower surfaces 9, 10 of the main blade 8 outward. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a wind turbine generator, and more particularly to a propeller type wind turbine generator.

  As an example of a propeller-type wind power generator, a wind turbine provided with a nacelle installed at the top of a tower, a windmill rotatably provided at the tip of the nacelle, a speed increaser and a generator provided in the nacelle A power generation device is known.

  In the propeller-type wind power generator having such a configuration, the wind turbine is configured by attaching a plurality of blades to the rotor head, and the wind turbine receives the wind and rotates to increase the rotational force of the wind turbine. The speed is increased by the speed machine and transmitted to the generator, and the generator is driven to rotate, whereby wind energy is converted into electric energy and taken out.

  The propeller-type wind power generator has an energy conversion efficiency of about 40% at maximum, and the energy conversion efficiency increases as the lift-drag ratio (ratio between lift and drag) of the wind turbine blade increases. Further, since the lift-drag ratio varies depending on the elevation angle of the blade, it is necessary to keep the elevation angle of the blade constant in order to obtain a constant energy conversion efficiency.

  As methods for keeping the elevation angle of a windmill blade constant, conventionally, a method for controlling the pitch angle of the blade, a method for making the windmill variable, a method for changing the size of the blade, a method for changing the wind pressure of the blade, etc. have been proposed. Yes.

  As a method for controlling the pitch angle of the wind turbine blade, for example, a pitch angle adjusting mechanism that is driven by hydraulic pressure is provided inside the rotor head of the wind turbine, and the pitch angle of each blade is adjusted by driving the pitch angle adjusting mechanism. A method configured as follows is proposed.

  Further, as a method of changing the windmill at a variable speed, for example, a method has been proposed in which the windmill is variable-speed by controlling the power supply frequency with an inverter.

  Furthermore, as a method for changing the size of the blade, for example, Patent Document 1 proposes a method in which the size of the blade is changed by inserting and removing an auxiliary member from the blade.

Furthermore, as a method of changing the wind pressure of the blade, for example, in Patent Document 2, a blade is formed in a cylindrical shape, and a drive mechanism for rotating the blade is provided inside the rotor head, and the cylindrical blade is moved by the drive mechanism. A method configured to be rotationally driven has been proposed.
JP 2003-269320 A JP 2005-256606 A

  By the way, as described in Patent Document 1, in the case of a windmill using a blade whose cross section is streamlined, the cross-sectional shape of the blade is formed into a thin streamline shape in order to increase energy conversion efficiency. Therefore, when the wind speed is low, sufficient lift cannot be obtained, the windmill cannot be sufficiently rotated, and it becomes difficult to extract desired electrical energy.

  On the other hand, the blade of the windmill described in Patent Document 2 does not cause the problem of wind speed unlike the blade having a streamlined cross section, and can sufficiently rotate the windmill even at a low wind speed. Since the lift-drag ratio cannot be increased, high energy conversion efficiency cannot be obtained as in a wind power generator using a windmill with a blade having a streamline cross section.

  The present invention has been made in view of the above-described conventional problems. Even when the wind speed is low, sufficient lift can be obtained, the windmill can be sufficiently rotated, and desired electrical energy can be obtained. It is an object of the present invention to provide a wind turbine generator that can obtain a high energy conversion efficiency and a high lift-drag ratio.

In order to solve the above problems, the present invention employs the following means.
That is, the invention according to claim 1 rotates a wind turbine in which a plurality of blades are attached to a rotor head, and transmits the rotational force of the wind turbine to a generator via a speed increaser to drive the generator. The blade is provided with a main blade having a streamline cross section, and is rotatably provided on the main blade, and a part of the blade is outward from the upper and lower surfaces of the main blade. And a driving means for rotationally driving the sub-blade.

  According to the wind turbine generator according to the present invention, the wind turbine includes the main blade having a streamlined cross section and the rotatable sub blade partially protruding from the upper and lower surfaces of the main blade. High energy conversion efficiency is obtained by the main blade that can be taken high, and by rotating the rotatable sub-blade by the driving means, sufficient lift can be obtained even when the wind speed is low. A constant high energy conversion efficiency can be obtained in a wide range of wind speeds.

  The invention according to claim 2 is the wind power generator according to claim 1, wherein the sub blade is cylindrical or columnar, and the longitudinal direction is along the longitudinal direction of the main blade. It is provided in the main blade, and a part of the peripheral surface protrudes outward from the upper and lower surfaces of the main blade.

  According to the wind turbine generator according to the present invention, the secondary blade is driven to rotate by the drive source, so that the Magnus effect can be generated at the peripheral surface portion of the secondary blade protruding from the upper and lower surfaces of the primary blade. Even if the wind speed is low due to the effect, sufficient lift can be obtained and high energy conversion efficiency can be obtained.

  The invention according to claim 3 is the wind power generator according to claim 1 or 2, wherein a plurality of the auxiliary blades are provided along a longitudinal direction of the main blade.

  According to the wind turbine generator according to the present invention, a plurality of sub blades are driven to rotate by a drive source, thereby generating a Magnus effect at each of the peripheral surface portions of the plurality of sub blades protruding from the upper and lower surfaces of the main blade. This Magnus effect can provide sufficient lift even when the wind speed is low, and high energy conversion efficiency can be obtained.

  As described above, according to the wind turbine generator of the present invention, the blade of the wind turbine is provided with the main blade having a streamline cross section and the main blade so as to be rotatable. Because it consists of a secondary blade that protrudes outward from the lower surface and a drive means that rotationally drives the secondary blade, high energy conversion efficiency can be obtained by the primary blade that can achieve a high lift-drag ratio, and a rotatable secondary blade is driven. By rotationally driving by means, a Magnus effect is produced in the portion of the secondary blade protruding from the main blade, and sufficient lift is obtained by this Magnus effect even when the wind speed is low. Therefore, by properly using the main blade and the sub blade according to the wind speed, a certain high energy conversion efficiency can be obtained in a wide range from a low wind speed to a high wind speed, and the desired electrical energy can be reliably obtained. become.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 5 show an embodiment of a wind power generator according to the present invention. FIG. 1 is a schematic view showing the entire wind power generator. FIG. 2 is a plan view of the blade of FIG. 3 is a cross-sectional view of the blade of FIG. 2 along the line AA, FIG. 4 is an explanatory view showing the rotation direction of the secondary blade, and FIG. 5 is an explanatory view showing the Magnus force generated by the rotation of the secondary blade.

  That is, the wind power generator 1 shown in the present embodiment is a propeller-type wind power generator, and as shown in FIG. 1, a nacelle 4 installed on the top of the tower 2 via a mount 3, and a nacelle 4 is provided with a wind turbine 5 rotatably provided at the tip of 4, a speed increasing device 19 provided inside the nacelle 4, and a generator 20 provided inside the nacelle 4.

  The windmill 5 is attached to a rotor head 6 connected to a main shaft (not shown) that is rotatably provided inside the nacelle 4, and is attached to the circumferential surface of the rotor head 6 so as to be radial with respect to the axis of the rotor head 6. In addition, three blades 7 each capable of adjusting the pitch angle, and a pitch angle adjusting means 18 for adjusting the pitch angle of each blade 7 provided inside the rotor head 6 are provided.

  As shown in FIGS. 2 and 3, each blade 7 is provided with a main blade 8, a sub-blade 14 rotatably provided on the main blade 8, and a sub-blade 14 provided inside the rotor head 6 to rotate. Drive means (not shown).

  The main blade 8 is formed of glass fiber reinforced plastic (FRP) or the like, and is formed in a substantially rectangular plate shape with a streamlined cross section as shown in FIGS. In this case, the main blade 8 has an upper surface 9 and a lower surface 10 formed in a predetermined streamline-shaped curved surface so that the cross section has a streamline shape over the entire length, and has a width from one end to the other end in the longitudinal direction. The overall width and thickness are set so that the thickness gradually decreases and the thickness decreases gradually.

  A cylindrical attachment portion 13 for attaching to the rotor head 6 is integrally provided at one end portion in the longitudinal direction of the main blade 8, and the attachment portion 13 is provided in an attachment hole ( The main blade 8 is rotatably attached to the peripheral surface of the rotor head 6 by being inserted into the not shown. The mounting portion 13 of the main blade 8 is connected to a pitch angle adjusting means 18 provided inside the rotor head 6, and the main blade 8 is rotated via the mounting portion 13 by driving the pitch angle adjusting means 18. Thus, the pitch angle of the main blade 8, that is, the pitch angle of the blade 7 can be adjusted.

  A rectangular attachment hole 11 penetrating between the upper and lower surfaces is provided in the central portion of the main blade 8 over substantially the entire length, and a later-described secondary blade 14 is rotatably provided in the attachment hole 11. The portion of the inner surface of the main blade 8 facing the mounting hole 11 is closed by a closing plate 12, and the blocking plate 12 prevents rainwater and the like from entering the main blade 8. The blocking plates 12 disposed at both ends in the width direction of the mounting hole 11 are formed with curved surfaces having a predetermined curvature in order to avoid interference with the auxiliary blade 14.

  As shown in FIGS. 2 and 3, the secondary blade 14 has a columnar shape or a cylindrical shape formed of glass fiber reinforced plastic (FRP) or the like, and the longitudinal direction is along the longitudinal direction of the main blade 8. As described above, a plurality of the main blades 8 are provided in a state of being arranged in a row in the mounting hole 11 at the center of the main blade 8.

  At the center of the plurality of sub blades 14, a support shaft 16 is provided integrally with the entire length thereof, and the support shaft 16 is provided in the mounting hole 11 of the main blade 8 at predetermined intervals. A plurality of sub-blades 14 are rotatably provided in the mounting hole 11 by being supported by the bearing 17.

  One end portion of the support shaft 16 penetrates the attachment portion 13 of the main blade 8 and protrudes into the rotor head 6, and one end portion of the protruding support shaft 16 is provided inside the rotor head 6. (Not shown), and a plurality of sub-blades 14 are configured to rotate integrally with the support shaft 16 by driving of the driving means.

  The drive means includes a drive motor, a connection mechanism that connects the output shaft of the drive motor and the support shaft 16, and a control means that controls the rotational speed of the drive motor, and drives the drive motor via the connection mechanism. By rotating the support shaft 16, the plurality of sub blades 14 are rotationally driven integrally with the support shaft 16. By adjusting the rotational speed of the drive motor by the control means, the rotational speed of the sub blade 14 can be adjusted.

  Each sub blade 14 protrudes outwardly (upward and downward in the figure) from the streamlined upper surface 9 and lower surface 10 of the main blade 8, and the upper surface 9 and lower surface 10 of the main blade 8. A part of the peripheral surface 15 of the auxiliary blade 14 protruding from the above can cause a Magnus effect to be described later when the auxiliary blade 14 rotates.

  Here, as shown in FIG. 5, when the rotating secondary blade 14 receives a head wind, the Magnus effect increases the flow speed of the wind and reduces the pressure on the side where the head wind and the rotation direction coincide with each other. On the opposite side, the flow velocity becomes slow and the pressure increases, and as a result, the secondary blade 14 receives a force directed to the matching side, and lift is generated in that direction.

  In the present embodiment, four sub blades 14 are provided in the mounting hole 11 of the main blade 8, but two, three, five or more sub blades 14 may be provided. . Alternatively, a plurality of blades 14 may not be provided in the attachment hole 11 of the main blade 8, and one sub-blade 14 may be provided over substantially the entire length of the attachment hole 11.

Next, the operation of the wind power generator 1 according to this embodiment configured as described above will be described.
First, when a wind with a low wind speed at which a sufficient lift cannot be obtained with the streamlined main blade 8 acts on the wind turbine, the sub blade 14 is rotated in the direction of the arrow by the driving means as shown in FIG. By driving, as shown in FIG. 5, a portion of the peripheral surface 15 projecting from the upper surface 9 and the lower surface 10 of the main blade 8 of the sub blade 14 causes a Magnus effect. Cause a strong lift. As a result, the windmill 5 can be sufficiently driven to rotate, so that desired electrical energy can be obtained. In FIG. 5, a indicates the rotational force of the windmill 5, b indicates the force of the blade 7, c indicates the Magnus force, and d indicates the rotational direction of the sub blade 14. In this case, the rotation speed of the sub blade 14 is set to an appropriate value according to the wind speed acting.

  On the other hand, when a wind with a high wind speed acting on the wind turbine cannot obtain a high lift / drag ratio by rotation of the secondary blade 14, the rotation of the secondary blade 14 is stopped and the wind is received by the main blade 8. Take a large ratio. As a result, the windmill 5 can be sufficiently driven to rotate, so that desired electrical energy can be obtained. In this case, an operation such as adjusting the pitch angle of the main blade 8 according to the wind direction is performed.

  In the wind power generator 1 according to the present embodiment configured as described above, the windmill 5 is generated by causing the Magnus effect to be increased by rotationally driving the sub-blade 14 when the wind speed is low, thereby increasing the lift. Is driven sufficiently to take out the desired electrical energy, and in the case of a high wind speed, the main blade 8 raises the lift-drag ratio so that the wind turbine 5 is sufficiently driven to take out the desired electrical energy. Thus, high energy conversion efficiency can be obtained within a wide range from a low wind speed to a high wind speed, and desired electrical energy can be reliably extracted.

It is the schematic which showed the whole one Embodiment of the wind power generator by this invention. It is a top view of the braid | blade of FIG. It is the sectional view on the AA line of the braid | blade of FIG. It is explanatory drawing which showed the rotation direction of the subblade of FIG.2 and FIG.3. It is explanatory drawing which showed the relationship between the rotation direction of a subblade, and Magnus force.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Wind power generator 2 Tower 3 Base 4 Nacelle 5 Windmill 6 Rotor head 7 Blade 8 Main blade 9 Upper surface 10 Lower surface 11 Mounting hole 12 Closure plate 13 Mounting portion 14 Sub blade 15 Peripheral surface 16 Support shaft 17 Bearing 18 Pitch angle adjusting means 19 Gearbox 20 Generator

Claims (3)

A wind turbine generator that extracts electrical energy by rotating a wind turbine with a plurality of blades attached to the rotor head, transmitting the rotational force of the wind turbine to the generator via the gearbox, and driving the generator. And
The blade includes a main blade having a streamline cross section, a sub blade that is rotatably provided on the main blade, and a part of the sub blade protrudes outward from the upper and lower surfaces of the main blade, and the sub blade is rotated. The wind power generator characterized by including the drive means to drive.   The sub-blade has a cylindrical or columnar shape, and is provided on the main blade so that a longitudinal direction thereof is along the longitudinal direction of the main blade, and a part of the peripheral surface is outside the upper and lower surfaces of the main blade. A wind power generator characterized by protruding in the direction. The wind turbine generator according to claim 1 or 2, wherein a plurality of the sub blades are provided along a longitudinal direction of the main blade.

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